Eastern Shipbuilding Group, Panama City, Fla., has completed the articulated tug-barge trailing suction hopper dredge unit consisting of the 433'x92'x36' hopper dredge Ellis Island and the 158'4"x52'x32'9" tug Douglas B. Mackie for Great Lakes Dredge & Dock Co. (GLDD), Oak Brook, Ill.
Ship Architects Inc., Daphne, Ala., handled the detail tug design and Bay Engineering Inc. handled the detailed dredge design. Both designs are based on an Ocean Tug & Barge Engineering ATB concept design.
Great Lakes entered into an estimated $94 million contract with Signal International back in 2012 to build what was billed as the first ATB trailing suction hopper dredge. The agreement eventually fell apart, and Great Lakes went looking for another yard to finish building the ATB — enter Eastern.
The tug’s main propulsion comes from two MAK 12M32C-T3 diesel engines, producing 7,831 hp each, connected to Schottel props through Overton Chicago marine gears. The MAKs also powers twin shaft generators each rated at 2,500 kW, 6,600 VAC. The tug is also equipped with a Caterpillar C32-T3 powered auxiliary generator, producing 730 kW of electrical power at 1,800 rpm, and a Cat C18-T3 550-kW emergency genset.
The tug is ABS classed Maltese Cross A1, AMS, ACCU, Oceans Towing Vessel Unlimited Service, ILO, SOLAS/IMO/MARPOL and USCG certified Dual-Mode ITB, 33/46CFR, Subchapters E, F, G, I, J, M, Q and S.
The barge has a hopper capacity of 15,000 cu. yds. and is fitted with twin Schottel STT2 electric, fixed-pitch bowthrusters, producing 800 hp each, powered by the shaft generators on the tug. The dredge pumps are powered by two, 5,000-hp EMD ME20G7C-T3 diesel engines on the barge.
The dredge is classed ABS Maltese Cross A1, AMS, Unmanned Cargo Barge and SOLAS/IMO/MARPOL certified. In addition, it is USCG certified 33/46CFR NVIC Publications, Subchapter I, Unmanned.
The tug and barge is connected by a Taisei coupler system.
David Simonelli, president, dredging division said in a prepared statement, “We are excited to take delivery of this advanced vessel which improves the competitiveness of our hopper group and represents a substantial reinvestment in our fleet. The Ellis Island significantly increases the U.S. commercial Jones Act hopper fleet capacity as the largest hopper dredge in the U.S. market, with a carrying capacity of 15,000 cubic yards.”
The Ellis Island and tug Douglas B. Mackie ATB was scheduled to depart Panama City, Fla., this week for the Mississippi Coastal Improvements Program project and begin operations on the long haul coastal restoration project.